LP#2051557: ignore deleted monograph parts when checking title holds

LP#2051557: ignore deleted monograph parts when checking title holds

This patch ensures that when "Require Monographic Part when Present"
is in effect, that deleted monograph parts are not taken into
account when checking whether a title-level hold is possible.

To test
-------
[1] Set up a bibliographic record that has at least one monograph
    part, then delete that part.
[2] Turn on the "Require Monographic Part when Present" library setting.
[3] Attempt to place a title-level hold on the record. Note that the
    following error is returned: "Require Monographic Part when Present"
[4] Apply the patch and repeat step 3. This time, the hold should
    go through.

Release-note: Ignore deleted monograp parts when checking title holds while "Require Monographic Part when Present" is on.

Signed-off-by: Galen Charlton <gmc@equinoxOLI.org>
Signed-off-by: Ruth Frasur Davis <rfrasur@library.in.gov>
Signed-off-by: Jason Etheridge <phasefx@gmail.com>